Repairing or replacing air ducts can help bring down your energy bills. The age of the HVAC system might be a factor, as well.


Every year, thousands of Arizona residents email Rosie Romero's website or call his radio show with questions about everything from how to prevent fires in their chimneys to what to do about the tree roots in their sewers. One of his goals is to provide answers that suit the specific lifestyle wherever someone lives in Arizona.

QUESTION: I own a typical 1,200 square-foot Tucson home built in the 1950s. It's built of cement block covered with stucco. But I have replaced the windows with dual pane construction and have put new insulation in the attic and walls. But my power bills are still outrageous. I'm on the utility's budget plan in which I pay the same amount every month, and my bills are running $220 a month consistently. Is it because I still have an air conditioner manufactured in 1990?

ANSWER: It sounds as if you have done all that you possibly can to keep the cooled air from leaking out of the interior of the house and keeping the warm air sealed outside. It could be a question of some repairs being needed on leaky ducts or it could be the result of having 1990 equipment which is less efficient than today's air conditioners. However, what you really need to do first is get off the utility's budget plan and start getting billed each month for the electricity you actually use. That is the only way that you can really tell when and why you are having problems. Having the same payment every month tends to mask what your issue might be. With the size of your house, you should really only be paying about $170 a month in the summer when you need air conditioning.

Q: I have a lot of what they call passive ventilation in my attic. I have three wind turbine vents as well as ridge vents and bird blocking vents. I've had all this for years; am I doing the right thing?

A: You're doing exactly what you should do to ventilate your attic. You don't want to put in electric fans to force-ventilate anything. You have the right amount of ventilation provided that you have R-30 to R-38 insulation installed in your attic.

Q: What would be wrong with forgetting all about having central air conditioning with ductwork running all over the house and going completely ductless?

A: By going ductless, you would have to install several wall-mounted, mini-split system air conditioners throughout your home. It would really only work in a very small house and would ultimately be much more expensive than installing central air conditioning with ducts that run to each room. The only real reason for installing an individual split system unit like this might be if someone added a room onto the house and didn't install ducts from the HVAC system.

Q: I recently had an energy audit done at my home. The conclusion was that there was 15 percent leakage of heated or cooled air from my ductwork and my lighting cans. What's the best way to seal up these problem areas? And where is the best source of information on this issue?

A: I suspect that the auditing company probably recommended a process of blowing a sealant into your duct system to correct the problem. In our opinion that is not your best option. The return on investment in this type of process is typically very low. Unless there are gaping holes in your ducts, what you probably need to do is to simply tighten all the fittings in your duct system to reduce any leakage going on. Contact an air-conditioning company in your area to check the fittings for you and be sure to share with them the findings of the audit company.

For more do-it-yourself tips, go to . An Arizona home building and remodeling industry expert for 25 years, Rosie Romero is the host of the syndicated Saturday morning Rosie on the House radio program, heard locally from 8-11 a.m. on KNST-AM (790) and -FM (97.1) in Tucson and KGVY-AM (1080) and -FM (100.7) in Green Valley. Call 1-888-767-4348.